This invention relates to .beta.-lactam compounds. In particular, this invention relates to 4-fluoroazetidinone compounds obtained from penicillins and to a process for the preparation thereof.
The .beta.-lactam antibiotics, the penicillins and the cephalosporins, are well known substances which are generally prepared by semi-synthetic methods. These antibiotics are bicyclic compounds having a 4-membered lactam ring fused to another heterocyclic ring. Recently, however, newer monocyclic .beta.-lactam antibiotics have been developed. Nocardicin, U.S. Pat. No. 3,923,977, is one example of a monocyclic .beta.-lactam antibiotic.
4-chloroazetidinones are used as intermediates in the process described by S. Wolfe, U.S. Pat. Nos. 3,948,927, 3,950,352, 4,013,653, and 4,071,512, in the preparation of the so-called 1-oxapenicillins and the corresponding 1-oxa(dethia)cephalosporins. Further, Narisada Heterocycles, Vol. 77, No. 2 (1977), pp. 839-849 reports the preparation of 1-oxa-.beta.-lactam antibiotics with 4-chloroazetidinones.
Since it is known that the four-membered .beta.-lactam ring is a key structural feature of the known .beta.-lactam antibiotics considerable research has been directed to finding new monocyclic .beta.-lactam compounds for use as antibiotics and as intermediates in the preparation of the new .beta.-lactam antibiotics.